The combination of organization, labeling, search and navigation systems within websites and intranets.[4]:4

Extracting required parameters/data of Engineering Designs in the process of creating a knowledge-base linking different systems and standards.

A blueprint and navigational aid to the content of information-rich systems.[7]

A subset of data architecture where usable data (a.k.a. information) is constructed in and designed or arranged in a fashion most useful or empirically holistic to the users of this data.

The practice of organizing the information / content / functionality of a web site so that it presents the best user experience it can, with information and services being easily usable and findable (as applied to web design and development).[8]

The difficulty in establishing a common definition for "information architecture" arises partly from the term's existence in multiple fields. In the field of systems design, for example, information architecture is a component of enterprise architecture that deals with the information component when describing the structure of an enterprise.

While the definition of information architecture is relatively well-established in the field of systems design, it is much more debatable within the context of online information systems (i.e., websites). Andrew Dillon refers to the latter as the "big IA–little IA debate".[9] In the little IA view, information architecture is essentially the application of information science to web design which considers, for example, issues of classification and information retrieval. In the big IA view, information architecture involves more than just the organization of a website; it also factors in user experience, thereby considering usability issues of information design.

About the term information architectRichard Saul Wurman wrote: "I mean architect as used in the words architect of foreign policy. I mean architect as in the creating of systemic, structural, and orderly principles to make something work — the thoughtful making of either artifact, or idea, or policy that informs because it is clear."[10]